Photographic material



Nov 26,19 6. R. B. cams Em 2,411,501

PHOTOGRAPHIC MATERIAL Fi led Dec. 6, 1944 34D 40D iii/7: 11

Rolandflenwwd (Joni/1w MZLZGPINVENTORS BY fy v ATTORMYY Patented Nov.26, 1946 UNITED STATES PATENT OFFICE PHOTOGBAPHIC MATERIAL RonaldBernard Collins, llford, and John Miller, Nottingham, England, assignorsto Ilford Limited; Ilford, England, a British company ApplicationDecember 6, 1944, Serial No. 566,823 In Great Britain December 20, 1943This invention relates to photographic mate rials and particularly tothe manufacture of dyesensitised photographic silver halide emulsions.Photographic silver halide emulsions have a certain naturalsensitivity-to light, butthis is restricted to a short range ofwavelengths in the The present invention is concerned withsupersensitising combinations. I vention, photographic: silverhalideemulsions are According to the insupersensitised by incorporating inemulsion a combination of a sensitising'dyestuirof the where R1 and R2are the same or different and are-alkyl or aralkyl groups orsubstitutedgroups of this type, R3 is hydrogen for'an alkyLoraralkylgroup, and Di and D2 are the same or difierent and are residues ofheterocyclic nitrogen nuclei I of the classes common in cyanine dyes, Ais an acid radicle, andn 1s nought or one, and a compound of the generalFormula II:

in I

where D3 is the residue of a :heterocyclic nitrogen ring (which may bethe'same. or different from D1 or D2) R4 is an alkyl, aralkyl orsubstituted group of this type, X is a carboxyl, carbox- 4 ylic ester,acyl or nitrile group, and Y is a car- I boxyl, carboxylic ester,nitrile 0r acrylic ester group, or Xand Y togethenformthe residue of a5-memb'ere'd 'keto-methylene ring, and hi nought orone. I The aboveterms, as used-in the present specification and claims, have thefollowing meaning:

Carboxyl means -(:0 OH Carboxylic ester means -8 0 Acyl means (H).

Nltrile means .LC I Acrylic ester, QCH;VCH C 0 O R where is ahydrocarbon radical. f

12 Claims.

2 V The groups R11, R2 and R4 are preferably lower alkyl radicles, i. e.radicles containing-not more than l'carbon atoms, eg. methyl or ethyl,or

hydroxy lower-alkylradicles, and the group R3, when not hydrogen, isalso preferably a lower alkyl radicle, e. g. methyl or ethyl. Thesegroups may, however, be higher alkyl radicles, or may be aralkylradicles such as benzyl or naphthylmethyl.

The residues D1, D2 and D3 may be selected from the residues ofthiazoles, oxazoles, selenasoles and their polycyclic homologues suchas' those of the benzene, naphthalene, acenaphthene and anthraceneseries, pyridine and its polycyclic homologues, such as quinoline andaand pnaphthaquinolines, lepidines, indolenines, dia- Zines, such aspyrimidines and quinazolines, diazoles (e. g. thio-Mr-diazele)oxazolines, thiazolines and selenazolines, The polycyclic compounds ofthese series mayalso be substituted in the carbocyclic rings with one ormore groups,

such as alkyl, aryl, amino, hydroxy, alkoxyand' methylene-'dicxy groups,or by halogen atoms,

The acid radicle A may be, for example, ch10.- ride, bromide, iodide,alkyl sulphate, alkyl-ptoluene sulphonate or perchlorate.

In the case of the compound of general Formula II, the groups'Xand Y,where ester groups, are preferably lower alkyl esters.

example, methyl, ethyl or .a higher alkylgroup, benzyl, naphthyl-methyl,phenyl' or'fnaphthyl. Where it is an acyl group it is preferably aresidue of a lower fatty acid, e. g. acetic or propionic .'acid. Where Xand Y together-form the residue of a 5-memberedketo-methylene ring thismay be, for example, a pyrazolone, thiopyrazolone, rhodanine, indandione'or hydantoin nucleus.

' 9 The following are examples of specific com- Y pounds which maybeemployed according to this I invention, the compounds being lettered tofacilitate subsequent reference:

Dyestuffs of general Formula I bocyanine iodide." B.3.3.9-triethyl-5.5-dichloro thiacarbocyanine chloride.

.C. 3.3-diethyl- 9-methyl --thiacarbocyanine bromide,

n. 3.3L9-tiiethyl 4.5 14*.54 'clibenzthiacarbocyanineiodide. E.3.3.Q-triethyl-oxacarbocyanine iodide.

' F. 3.3-dimethyl-9-ethy1-4.l'dichlor thiacarbocyanine iodide. G.3.9-diethyl-3'-methyl 4.4 dichlor-thiacarbocyanine iodide;

3.3-diethyl-9-methyl 4.4 dichlor-thiacarbocyanine iodide.

Where the o group X is alkyl, aryl or aralkyl it may be, for

Compounds of general Formula II 1?.Ethyl-3-methyl-dihyclrobenzthiazolyl-Z-cyanacetate havin the formula:

CN N/ C O O C2155 quinothiacarbocya- Q,3-methyl-dihydrobenzthiazolyl-2-aceto acetic ester having the formula:

R. 3-ethyl-dihydrobenzthiazolyl-Z-ethyl acetate having the formula:

ON C=C N/ C O O CzHs I Call S. 3-methvl-dihydro-benzoxazolyl-2-ethy1cyanacetate having the formula:

ON o 01H.

T. 3-methyl-4:5-benzbenzthiazole-2-ethyl cyanacetate having the formula:

cyan- V. 3-methyl-dihydrobenzthiazolyl-2-malonic ethyl ester having theformula:

4 W. 4.2 (3' methyl-dihydrobenzthiazolyl)-1-phenyl-3-methyl-5-pyrazolone having the formula:

CuH

X. 2.2'-(3' methyl-dihydrobenzthlazolyl) 1.3-indandione having theformula:

I Y. 3-methyl-dihydrobenzthiazolyl-Z-acetone dicarboxylate having theformula:

Z. 3-methy1-5.6.-dimethoxy dihydrobenathiazolyl- 2-cyanacetic ethylester having the formula:

ZA. 3-Inethyl-dihydrobenzthiazolyl-2-glutaoonic diethylester having theformula:

'23. 2-dicyanmethylene-3-methyl-dihydrobenzthiazole having the formula:

CH: ZC. 3-methyldihydrobenzselenazolyl-2-ethy1 cyanacetate having theIII CH3 formula:

ZD. l-ethyl-dihydroquinolylidene-2-malonic eth' yl ester having theformula:

COOC HF,

02H: The optimum quantity of the dyestuif of general Formula I to be inwill generally be of th 1 in 2000 solution of corporated in the emulsione order of 5 to 50 cc. of a, the dyestuff per litreof emulsion. Theoptimum quantity of the compound of general Formula II will generallyfall within the same range, but in many cases optimum results areobtained where the quantity of such compound is somewhat greater thanthe quantity of dyestuff used.

The following examples illustrate the invention. In these examples theemulsions containing the dyestuff of general Formula I and compound ofgeneral Formula II were tested for speed to daylight and to red light.This latter figure was obtained, by exposing the emulsions to whitelight passing through a filter. which cuts off all radiation ofwavelengths less than 600 m The increase'in'the red speed shown by thesupersensitised emulsions in comparison with emulsions containing onlythe dyestuffs of general Formula I affords a measure of thesupersensitising eifect obtained.

Examples In these examples the compounds of Formulae I and II arereferred to by the letters given to them above.

The combinations of dyestuif and supersensitising compound wereincorporated in a gelatin silver iodobromide emulsion containing about6.5 gms. of silver halide (calculated as silver) per litre of emulsion,during the manufacture of the emulsion, and the resulting emulsion wascoated on glass and the speed values referred to above were determined.The results are set out in the following table:

Quantity Quantity of i 31 1 c ?i 1 mm a '0mormu a gi 11n cc;b[ g oumi{if II1i n clrisdooi' Redd in ormu a in spee mum I solution II solutionSpeed per litre of per litre of emulsion emulsion A None 92 15 A 15 P 7107 23 A 15' Q 28 105 24 A 22 None 145 J 38 A' 22 T 15 170 60 B. 22 None135 50 B 22 P 30 165 78 B 22 None I45 50 B 2-2 R 32 180 I 60 B 22 S 4145 55 B 22 T 32 160 58 C 22 None 135 15 C 22 '1 14 155 19 D 22 None 13449 D 22 P 55 155 80 E 22 None 110 11 E 22 P 28 135 19 K 15 None 120 17 K15 P 30 330 *160 K 15 None 45 6 K 15 Z 30 93' v 68 The speed valuesgiven in the foregoing table are substantially linearly related, i. e.are in direct proportion. It will be apparent from the data given in theforegoing table that the super sensitising combinations of thisinvention in manycases not only impart an increased sensitivity to theemulsion in the sensitising region of the dyestuff of Formula I, butactually effect an increase in the overall sensitivity oi'the emulsionas shown by the generally increased daylight speed. Moreover, theinclusion of the compounds of Formula II frequently produces a markedchange in the distribution of the spectral sensitivity of the emulsion.These effects are illustrated by the accompanyingdrawing which showsspectral sensitivity curves for the emulsions of certain of theforegoing examples. 7

In the drawing Fig. 1 shows thespectral sensitivitycurveoi theemulsions. oiv Examples: is (full line) and 1b (dotted line). Fig. 2shows the spectral sensitivity curve of the emulsion of Examples 3a(full line) and 3b (dotted line). Fig. 3 shows the spectral sensitivitycurve of the emulsion of Examples 6a (full line) and 6b (dotted line).Fig. 4 shows the spectral sensitivity curve of the emulsion of Examples7a (full line) and 7b (dotted line). Fig. 5 shows the spectralsensitivity curve of the emulsion of Examples 8a (full line) and 8b(dotted line). Fig. 6 shows the spectral sensitivity curve of theemulsion of Examples 9a (full line) and 9b- (dotted line).

While this invention is of particular value in connection with thesupersensitizing. of silver halide emulsions in gelatin, other bindingcolloids for the emulsion may be employed, for example polyvinylalcohol, polyvinyl acetals, farhydrolysed cellulose esters and the like.

What we claim is:

1. Silver halide photographic emulsions containing a sensitizingdyestuff of the general where R1 and R2 are each selected from the groupconsisting of alkyl and aralkyl groups, R3 is selected from hydrogenatom, alkyl and aralkyl groups, D1 and D2 are each selected from thegroup consisting of residues of heterocyclic nitrogen nuclei, A is anacid radicle and n is selected from the group consisting of nought andone, and a compound of the general formula:

where D3 is selected from the sameclass as D1 and D2, R4 is selectedfrom the same class as R1 and R2, X is selected from-the classconsisting of the carboxyl, carboxylic ester, acyl and nitrile groups,and atoms which with-Y form the residue of a 5-membered keto-methylenering, and Y is selected from the group consisting of carboxyl,

carboxylic ester, nitrile and acrylic ester groups and atoms which withX form the residue of a S-membered keto-methylene ring, and n isselected from the group consisting of nought and'oner 2. Silver halidephotographic emulsions containing a sensitizing dyestuff of the generalformula: V I

R1 R: A

whereDa is selected. fromthe same, class, asDi and R4. is; selected.from the same class as the group consisting of the and one.

3. Silver halide photographic emulsions containing a sensitizingdyestuff of the general formula:

R1 R2 A where R1 and R2 are each selected from the group consisting ofalkyl and aralkyl groups, R3 is selected from the group consisting ofthe hydrogen atom, alkyl and aralkyl groups, D1 and D2 are each selectedfrom the group consisting of residues of heterocyclic nitrogen nuclei,A, is an acid radicle and n is selected from the group consisting ofnought and one, and a compound of the general formula:

where D; is a residue of an azole nucleus, R4 is selected from the sameclass as R1 and R2, X is selected from the class consisting of thecarboxyl, carboxylic ester, acyl and nitrile groups and atoms which withY form the residue of a 5- membered keto-methylene ring, and Y isselected from the group consisting of carboxyl, carboxylic ester,nitrile and acrylic ester groups and atoms which with X form the residueof a 5-membered keto-methylene ring, and n is selected from the groupconsisting of nought and one.

4. Silver halide photographic emulsions containing a sensitisingdyestufi of the general formula:

where R1 and R2 are each selected from the group consisting of alkyl andaralkyl groups, R3 is selected from the group consisting of the hydrogenatom, alkyl and aralkyl groups, D1 and D2 are each the residues of azolenuclei, A is an acid radicle and n is selected from the group consistingof nought and one, and a compound of the general formula:

wher D3 is a residue of an azole nucleus, R4 is selected from the sameclass as R1 and R2, X is selected from the class consisting of thecarboXyl, carboxylic ester, acyl and nitrile groups and atoms which withY form the residue of a 5- membered keto-methylene ring, and Y isselected from the group consisting of carboxyl, carboxylic ester,nitrile and acrylic ester groups and atoms which with X form the residueof a 5-membered keto-methylene ring, and n is selected from the groupconsisting of nought and one; 7

l 5. Silver halide photographic emulsions con- 8 taining a sensitisingdyestufi which is a compound of the general formula:

where R1 and R2 are each selected from the group consisting of alkyl andaralkyl groups-R3 is selected from the group consisting of the hydrogenatom and alkyl and aralkyl groups, M1 and M2 are each the residue of athiazole'nucleus and A is an acid radicle, and a compound of the generalformula:

where M; is a residue of a thiazole nucleus, R4 is selected from thesame class as R1 and R2, X is selected from the class consisting of thecarboxyl, carboxylic ester, acyl and nitrile groups and atoms which withY form the residue of a 5-membered keto-methylene ring, and Y isselected from the group consisting of carboxyl, carboxylic ester,nitrile and acrylic ester groups and atoms which with X form the residueof a 5- membered keto-methylene ring.

6. Silver halide photographic emulsions containing a sensitisingdyestuff which is a compound of the general formula:

where R1 and R2 are each selected from the group consisting of alkyl andaralkyl groups, R3 is se lected from the group consistin of the hydrogen atom and alkyl and aralkyl groups, M1 and M2 are each the residue ofa benzthiazole nucleus and A is an acid radicle, and a compound of thegeneral formula:

where M3 is a residue of a, benzthiazole nucleus,

where R1 and R2 are. each lower alkyl groups, R3 is aloweralkylgroup,.l\/ JL-and-M2;a1Te cathihe 'is a lower alkyl group,

'is a lower alkyl group,

residue of athiazole nucleus and A is an acid radicle, and a compound ofthe general formula:

where M: is a residue of a thiazole nucleus, R4 X is selected from theclass consisting of the carboxyl, carboxylicester, acyl and nitrilegroups and atoms which with Y form the residue of a -memberedketo-methylene ring, and Y is selected from the group con-, sisting ofcarboxyl, carboxylic ester, nitrile and acrylic ester groups and atomswhich with X form the residue of a 5-membered keto-methylene ring.

8. Silver halide photographic emulsions containing a sensitising poundof the general formula:

where R1 and R2 are each lower alkyl groups, R3 is a lower alkyl group,M1 and M2 are each the residue of a benzthiazole nucleus and A is anacid radicle, and a compound of the general formula:

,s X i where R1 and R2 are each lower alkylgroups, R3 M1 and M2 are eachthe residue of a thiazole nucleus and A is an acid radicle, and acompound of the general formula:

ring.

where M: is a residue dyestuff which is a com- 7 group, and

10. Silver halidephotographic emulsions containing a sensitisingdyestufi which is a compound of the general formula:

where R1 and R2 are each lower alkyl groups, R3 is a lower alkyl group,M1 and M2 are each the residue of a thiazole nucleus and A is an acidradicle, and a compound of the general formula:

where R1 and R2 are each lower alkyl groups, R3

is a lower alkyl group, M1 and M2 are each the residue of a benzthiazolenucleus and A is an acid radicle, and a compound of the general formula:

where M3 is a residue of a benzthiazole nucleus, R4, is a lower alkylgroup, X is a carboxylic ester group, and Y is selected from the groupconsisting of carboxyl, carboxylic ester, nitrile and acrylic estergroups and atoms which with X form the residue of a 5-memberedketo-methylene ring.

12. Silver halide photographic emulsions containing a sensitisingdyestuff which is a compound of the general formula:

R1 B2 A where R1 and R2 are each lower alkyl groups, R; is a lower alkylgroup, M1 and M2 are each the residue of a benzthiazole nucleus and A isan acid radicle, and a compound of the general formula:

where M3 is a residue of a benzthiazole nucleus, R4 is a lower alkylgroup, X is a carboxylic ester Y is a nitrile group.

RONALD BERNARD COLLINS. JOHN MILLER.

